Semiconductor device fabrication involves the forming of different components on a substrate using a variety of techniques, such as deposition, patterning, and etching. One component in semiconductor devices is a contact for coupling a layer of material to the underlying substrate or another layer. Depending on the particular application and the desired function, contacts may be holes, vias, channels, or other geometric structures.
As semiconductor devices become more complex with greater component density, new techniques are developed to provide higher fabrication tolerances. For example, a technique has been developed for a self-aligned contact that reduces the spacing between adjacent gates separated by the self-aligned contact. Other techniques may also be used to improve component density on a semiconductor device. However, these techniques demand accurate and controlled removal of material to create a contact without interfering with surrounding components.